Mobile communication for cellular networks is an integral part of modern life. With more and more terminals connecting to cellular networks, reducing power consumption of the terminals is a major requirement.
Techniques are known to reduce power consumption of a terminal by implementing discontinuous reception of messages transmitted by the cellular network via a radio link of the cellular network. One example of implementing discontinuous reception is the Discontinuous Reception Cycle (DRX) according to the Third Generation Partnership Project (3GPP) Technical Specification (TS) 36.321 V12.7.0 (2015-09). Here, a terminal in idle state discontinuously monitors the Physical Downlink Control Channel (PDCCH) according to the 3GPP Long Term Evolution (LTE) Evolved Universal Terrestrial Radio Access (E-UTRA) radio access technology (RAT), see, e.g., 3GPP TS 36.211 V12.7.0 (2015-09). The PDCCH is utilized for transmission of control data via the radio link. In particular, a cycle of the DRX comprises an On_Duration (active period) and an inactive period. The terminal selectively listens for downlink control data during the active period; during the inactive period, a protocol stack implemented for receiving data and/or an analog front end and/or a digital front end of the terminal are at least partially powered down to reduce power consumption.
However, such techniques face certain restrictions and drawbacks. Because reception of control data is restricted to the active period, such a protocol is vulnerable to missed detection of control data communicated on the PDCCH. In particular, where the control data comprises PDCCH commands such as downlink (DL) assignments or uplink (UL) grants specifying resources for communicating payload data via the radio link, successful transmission of the payload data can be considerably delayed.
In particular, where the payload data is associated with a service implemented by the cellular network and the terminal, the service having a quality of service (QoS) requirement corresponding to a certain latency, it can be difficult to fulfill this QoS requirement. E.g., the latency of communicating the payload data may be influenced by a periodicity of the DRX. E.g., where communication of control data comprising a PDCCH command has failed, sometimes it may be required to postpone retransmission of the PDCCH command to the next active period of the DRX.